Straightening machines with hyperbolic rolls



Jan. l0, 1956 R. HEIN-rz STRAIGHTENING MACHINES WITH HYPERBOLIC ROLLS 6 Sheets-Sheet 1 Filed Aug. 16, 1950 Jan. l0, 1956 R. HEINTZ STRAIGHTENING MACHINES WITH HYPERBGLIC ROLLS Filed Aug. 1e, 195o 6 Sheets-Sheet 2 Jan. l0, 1956 Filed Aug. 16, 1950 R. HEINTZ STRAIGHTENING MACHINES WITH HYPERBOLIC ROLLS 6 Shets-Sheet 3 In Ven four /'e #Eff/fz Jan. 10, 1956 R. HEIN-rz STRAIGHTENING MACHINES WITH HYPERBOLIC ROLLS Filed Aug. 16, 1950 6 Sheets-Sheet 4 Jan. 10, 1956 R. HElNTz STRAIGHTENING MACHINES WITH HYPERBOLIC ROLLS Filed Aug. 16. 195o 6 Sheets-Sheet 5 Jan. l0, 1956 R, H'EzlN-rz 2,730,158

STRAIGHTENING MACHINES WITH HYPERBOLIC ROLLS Filed Aug. 16, 1950 6 Sheets-Sheet 6 In mei? for if e #ff/77% l signed to deal with 'large-,diameter bars.

United States Patent O STRAIGHTENING MACHINES WITH HYPERBOLHC ROLLS Rene Heintz, Louvroil, France, assigner to LouvroilMontbard Aulnoye, Paris, France, socit anonyme Application August 15, H50, Serial No. 179,667

Claims priority, application France August 25, 1949 4 Claims. '(Cl. 15S-9i) Applicant is aware of machines adapted to straighten .cylindrical bars or tubes in which rolls are used having the shape of single'napped hyperboloids. In -these machines the product to be straightened rests on a pair of driving rolls located at ya certain distance from each other while a central roll located on ythe opposite side 'is intended to produce the straightening sag. The `bars or tubes are moved along la helical path by means of a pair of counter rolls mounted opposite the driving rolls, coaction with the driving rolls being obtained vby a `slight rolling of the products.

Such an arrangement is quite suitable for the straight ening of cylindrical bars or tubes.

This, however, is not the case with bars of ovalized or out-of-round section as obtained by hot-rolling. Where the distance between the work rolls and the related back-up rolls is adjusted to the .minor diameter of the bar, abnormal stresses are Aset up in the machine due .to `the deformations necessary in order that the major diameter can be obtained. Where the said distanceis adjusted to the major diameter, the bar product is no longer moved along when it is presented with its minor diameter between the rolls.

It has been ascertained according to the present invention that the vback-up rolls should preferably Vbe mounted resiliently, which makes it possible to control the stresses `set up as a consequence ofa given difference between the Idiameters of an `out-oif-.round lsection taken as a `limit case and therefore to exactly calculate the strength of the machine parts.

A further advantage of this arrangement is htat lthe power consumption is limited to the minimum consistent with a satisfactory straightening effect.

O11 the other hand, the round bar rolling tolerances are such that practically an ovalization `of the section is objectionable only with diameters larger than 50 mm. or so.

The manipulation of such bars is quite laborious, so that conventional straightening mills have to be equipped with a takefin and a takefout mechanism in order to facilitate the operation. These auxiliary mechanisms considerably increase the cost of a straightening mill de- In order to overcome this difficulty a combination 4,designed especially for the `straightening ,ovalized large-diameter bars has been adopted as will be .explained hereinafter. In this combination no auxiliary means are provided for taking the bars `in and out since these functions are performed automatically by the straightening mill itself.

The present invention has for its object a straightening mill with hyperbolic rolls adapted -to deal-with 'heavy bars or tubes having an ovalized section which is characterized in that means are provided to quickly move the take-in .work roll and back-up roll and the takeout work roll and back-,up roll. The bar material to be straightened is introduced `sidewise between the take-.in YQ-fk and back-up rolls purposely mcved, apart from. Que another, and this. simply by allowing the said bar 2,730,158 Patented Jan. 1 0, 195.6

material to roll down a bar take-in table. The material thus taken in is moved along down to the end of its travel by the work rolls and the companion back-up rolls, all `these pairs of rolls being spaced lengthwise of an arched frame, at least one set of said rolls being mounted resiliently, whereby an uninterrupted moving-along of the material to be straightened is assured irrespective 'of its degree of ovalization.

The removal of the straightened material is effected simply by allowing it to roll down a discharge table provided at the end of the frame.

A prefered embodiment of the present invention will now be described for the purpose of exemplication land by no means of limitation, reference being had to the appended drawing in which:

Figure l is a vertical sectional view o f the mill taken on the line I-l in Fig. 2, which is the axis of travel of the material to be straightened.

Figure 2 is a plan View of the back-up roll adjusting means, parts being shown in sectional view taken on line H*H in Fig. 3.

Figure 3 is an elevational end view.

Figures 4 and 5 are end views of the bar take-in and takeout mechanisms respectively.

Figure 6 is a diagrammatic plan view of the whole zar-straightening mill.

The take-in and discharge tables are omitted in Figs. l and 3, only the bars present on said tables being diagrammatically represented in Fig. 2.

The straightening mill is composed primarily of an arched frame i, a pair of work rolls 2 and 52 driven through the extension shafts 3 and 53, the step-down gear 4 by the motor 5, a sag roll 6 and back-up rolls 7, 57. The work rolls 2, S2, the sag roll 6 and the back-up rolls 7, 57 are angularly movable each in a horizontal plane through its own axis in such a manner that its hyperboloid skirt shall conform to the outline of the material to be straightened.

The arched frame l, as may be seen in Figs. 2 and 6, is provided `with skew ends in the vicinity of which extend arch end portions having a pier on one side only. In this way, a rst free passageway lis left op one side of the axis of travel of the work pieces for sideward engagement of the work pieces between the take-in rolls 2, 7, and a-second similar free passageway is left for sideward removal of the work pieces from between the take-ont rolls 52, 57.

The back-up rolls 7 and 57 are carried by air cushioned pistons 8, 5S slidable in cylinders 9, 59. The downward travel of the pistons 8 and 58 is limited by the engagement of the tops 108, SS of said pistons with pistons 10, -69 located in compressed air cylinders 11, 61, bored respectively in the pistons 8, 58. Chambers lll, `i are delimited above said pistons 10, v60 in the cylinders 1i, 6l to which compressed air can be supplied through ducts 2li, 261. The position of the pistons 1Q, 6i) can be adjusted with the aid of the ypiston rods 12, 62, bevel gear sets 14, 64, shafts 15, v65, bevel gear sets 16, 66 and spur gear wheels i7, 67, i8, 68 and 19.

The gear wheel 19 is rotated manually by means of the hand wheel 2t). On the other hand the sag roll ,6 is adiustable vertically through the medium of a nut 2,1, a spindle 22, a bevel gear set 23, a shaft 24 and a bevel Igear set 25.

Claw couplings 26, 27, 28 are provided whereby the positions of the back up rolls 7, 6, 57 can be adjusted either separately or all together simply by manipulating the hand wheel 2).

The vbars or tubes 29 to be straightened arel laid..(see`- Fig. 4) on a take-in table 30parallel with the axis of travel and can be displaced by rolling down the same in parallel motion at right angles to said axis. A bar takein guideway 31 is provided along the edge of said table 30 colinear with the axis of travel. The articles 29 to be straightened are laid on the table` 30 parallel with the axis of travel in such a manner that their leading ends to be caught between the take-in rolls are positioned slightly beynd the plane through the axis of the take-in work roll 2 at right angles to the direction of travel. In this way, at the moment when the article is run in, parallel motion down the table into the bar take-in guideway 31, its leading end passes through the free passageway left by the skew entrance of the arched frame 1 for the sideward engagement of the bar 29, and can be caught between the bar take-in rolls 2, 7 previously moved apart from each other for that purpose. Arranged at the opposite end of the mill beyond the rolls 52, S7 and colinear with the axis of travel is an angle iron 32 the lower horizontal flange of which is extended with an inclined discharge table 33 by which the bars 29 are lcd into a basket 34. The ends of the bars 29 pass through the free passageway left at the rear skew end of the arched frame 1.

The vertical iange at the angle from 32 provides a side stop for the article being straightened.

The back up rolls 7, 57 are urged towards the work rolls 2, 52 by the action of the air pressure present in the cylinders 9 and 59. The rolls can be moved away as desired by the introduction of compressed air into the chambers 111, 161 between the xed pistons 10, 60 and the tops 108, 15S of the movable pistons 8, 58 which carry the said back-up rolls 7, 57.

With the machine at rest, the distance between thebar take-in rolls 2, 7 and between the bar take-out rolls 52, 57 is adg'usted to a value slightly less than the minimum diameter of the products to be straightened. Under such conditions the pressure set up by the rolls 9, 59 can be exerted uninterruptedly during the straightening process. Operation of the work rolls 2, 52 on the articles to be straightened is obtained without abnormal stresses being generated and corkscrew motion progresses without jerking. Each time the section is caught by the roller pairs 2, 7 and S2, 57 the rolls 7 and 57 will retract slightly while compressing the air pressure present in the cylinders 9, 59.

In order to engage a bar 29 resting on the grate-like take-in table 30 it is merely necessary to lift the back-up roll 7 by admitting compressed air into the chamber 111 between piston 10 and the portion 108 of piston 8 while setting the cylinder 9 into communication with the atmosphere. guideway 31 so that its leading end shall come to a position between the rolls 2 and 7. The pressure in chamber 11,1 is then released while compressed air is admitted into the cylinder 9. The piston 8 will then force the back-up roll 7 outwards into engagement with the A bar and press it against the work roll 2 and will thereby cause it to be moved ahead in corkscrew-like motion.

The end of the bar thus moved ahead then passes successively opposite the sag roll 6 and is caught between the take-out work roll 52 and the companion back-up vrall 5,7. From that moment on the straightening process commences and continues until the trailing., end of the bar leaves the take-in work roll 2 the pressure exerted by the take-out back-up roll 57 maintains the helical motion which only ceases when the bar is no longer acted upon by said lback-up roll. In order to completely disengage the bar from the mill the back-up roll 57 is lifted by relieving the pressure in cylinder 59 and admitting air pressure into the chamber 161 between piston 60 and the top side 158 of piston 58. Pushing the bar 29 sidewise by hand or with the aid of a. mechanism (not shown) is sufficient to cause it to clear the angle iron 32 and roll down the inclined table 33 into the basket 34.

It is not necesary to Wait until the bar 29 is completely The bar 29 is then rolled down into the 4 out of the mill to introduce a new bar between the bar take-in rolls 2, 7.

The machine according to this invention makes it possible conveniently to straighten out of round large-diameter bars or thick walled tubes. The possible ovalized condition of the section has no inuence upon a satisfactory operation of the mill since the take-in and take-out back-up rolls are cushioned with compressed air and thereby can rise or sink according to the diameters of the material to be straightened while being positively moved along.

The arched form of the frame is particularly convenient for the direct introduction of the articles between the take-in rolls and for the removal thereof after being straightened, by allowing them to roll down, a simple inclined grate.

The mill described hereinbefore comprises a pair of work rolls the companion back-up rolls of which are acted upon by compressed air. It would obviously remain within the scope of the invention to modify the arrangement of the frame, the design of the adjusting means, the number of workand the back-up rolls, the direction of travel of the articles or to substitute the roll-actuating compressed-air-operated means by any other single or double-action elastic means; a loading spring may be used instead of compressed air; any uid other than air may also be used.

It is also within the scope of the present invention to substitute the means adapted to move the back-up rolls away from the work rolls (which are fixed with respect to the frame) e. g. by means adapted to move the work rolls away from the back-up rolls (which can then be fixed) by cushioning the former instead of the latter, or by cushioning both, or to adopt any other combination in which the work roll and the companion back-up roll can be moved towards or away from one another, at least one of them being mounted resiliently.

What I claim is:

l. A machine for straightening cylindrical work pieces by passing the same between rolls with concave peripheries, which said machine comprises a frame having the form andan arch with skew ends in the vicinity of which extend arch end portions having a pier on one side only, a plurality of rolls mounted under the arch constituted by the frame, said plurality including in the inlet end portion of the arch a pair of work piece take-in rolls composed of a lower work roll and of an upper and vertically shiftable back-up roll and in the outlet end portion of the arch a pair of work piece take-out rolls composed and mounted similarly to the pair of take-in rolls, means for actuating the work rolls, quick-action means for shifting upwards each vertically shiftable back-up roll, for shifting the same downwards in the direction of the companion work roll and for resiliently urging it in said direction, a work piece inlet-guide arranged ahead of the take-in rolls, a sloped table for the rough work pieces, partially engaged in the inlet end-portion of the arch opposite to the single pier of said end-portion, said table having its lower edge along the inlet guide and the take-in work roll and being thereby adapted for causing a sideward rolling motion of the rough work pieces towards the inlet guide and the engagement of the fore-end of said work pieces between the take-in work roll and the upwards shifted companion roll, a work piece outlet guide arranged in the rear of the'take-out rolls, and a sloped table partially engaged in the outlet end portion of the arch opposite to the single pier of said end portion, last said table having its upper edge along the take-out work roll and the outlet guide and being thereby adapted for removing the straightened bars by sideward rolling motion thereof when the take-out back up roll has been shifted upwards.

2. In a machine for straightening cylindrical work pieces bypassing the same between rolls with concave peripheries arranged along an axis of travel of the work pieces, a pair of work piece take-in rolls composed of a lower work roll and a vertically shiftable upper back-up roll and a similar pairof work piece take-out rolls, a support for said pair of take-in rolls leaving a free passageway on one side of the axis of travel of the work pieces for sideward engagement of said work pieces between said take-in rolls, a support for said pair of take-out rolls leaving a free passageway on one side of the axis of travel for sideward removal of said work pieces from between said take-out rolls, a kwork piece inlet guide arranged ahead of the take-in roll, a work piece outlet guide arranged in the rear of the take-out rolls, a sloped table for the rough work pieces having its lower edge along the inlet guide and the take-in work rolls and located on the same side of said axis of travel as the free passageway left by the support of the' take-in rolls, thereby adapted to cause a sideward rolling motion of the rough work pieces towards the inlet-guide and the engagement of the foreend of said work pieces between the take-in work roll and the companion back-up roll vertically shifted apart, and a sloped table having its upper edge along the take out work rolls and the outlet guide, the latter said sloped table being located on the same side of said axis of travel as the free passageway left by the support of the take-out rolls and being thereby adapted to remove the straightened bars by sideward rolling motion thereof.

3. In a machine for straightening cylindrical work pieces by passing the same between rolls with concave peripheries arranged along an axis of travel of the work pieces, a pair of work piece take-in rolls composed of a lower work roll and of a vertically shiftable upper backup roll, a support for said pair of take-in rolls leaving a free passageway on one side of the axis of travel of the work pieces for sideward engagement of said work pieces between said take-in rolls, a work piece inlet-guide arranged ahead of the take-in rolls, and a sloped table for the rough work pieces having its lower edge along the inlet-guide and the take-in work roll and located on the same side of said axis of travel as the free passageway left by the support of the take-in rolls, thereby adapted to cause a sideward rolling motion of the rough work pieces towards said inlet guide and the engagement of the foreend of said work pieces between the take-in work roll and the companion back-up roll vertically shifted apart.

4. A machine for straightening cylindrical work pieces by passing the same between rolls with concave peripheries arranged along an axis of travel, said machine comprising a frame, a plurality of rolls mounted in said frame, said plurality including at the one end of the machine a pair of work piece take-in rolls composed of a lower work roll and of an upper and vertically shiftable back-up roll and at the other end of the machine a pair of work piece take-out rolls composed and mounted similarly to the pair of take-in rolls, said frame leaving a first free passageway on one side of the axis of travel of the work pieces for sideward engagement of said work pieces between said take-in rolls, and leaving a second free passageway on one side of the axis of travel for sideward removal of said work pieces from between said take-out rolls, means for actuating the work rolls, quickaction means for shifting upwards each vertically shiftable back-up roll, for shifting the same downwards in the direction of the companion work roll and for resiliently urging it in said downward direction, a work piece inlet guide arranged ahead of the take-in rolls on the axis of travel, a work piece outlet guide on the same axis in the rear of the take-out rolls, a sloped table for the rough work pieces having its lower edge along the inlet-guide and the take-in work roll and located on the same side of said axis of travel as the said first free passageway left by the frame, thereby adapted to cause a sideward rolling motion of the rough work pieces towards the inletguide and the engagement of the forward ends of said work pieces between the take-in work roll and the upwards shifted companion roll, and a sloped table having its upper edge along the takeout work roll and the outlet guide and located with respect to the axis of travel on the same side as the said second free passageway left by the frame, thereby adapted to remove the straightened bars by sideward rolling motion thereof when the takeout back-up roll has been shifted upwards.

References Cited in the tile of this patent UNITED STATES PATENTS 850,810 Worth et al. Apr. 16, 1907 1,071,945 Moon Sept. 2, 1913 1,100,695 Ofutt June 16, 1914 1,946,933 Diescher Feb. 13, 1934 2,347,175 Dervey Apr. 25, 1944 2,517,344 Picton et al. Aug. l, 1950 FOREIGN PATENTS 508,210 Germany Sept. 25, 1930 

